Investment Securities, at Fair Value (Narrative) (Details) $ in Thousands	Sep. 30, 2015 USD ($) security	Dec. 31, 2014 USD ($) security
Schedule of Available-for-sale Securities [Line Items]
Investment securities, at fair value | $	$ 54,455	$ 58,646
CMBS [Member]
Schedule of Available-for-sale Securities [Line Items]
Number of securities owned	10	10
Investment securities, at fair value | $	$ 54,455	$ 58,646
Number of securities with fair value below amortized cost	3
CMBS [Member] | Minimum [Member]
Schedule of Available-for-sale Securities [Line Items]
Interest rate	5.88%
CMBS [Member] | Maximum [Member]
Schedule of Available-for-sale Securities [Line Items]
Interest rate	8.95%